繞過 Screensaver Lock 的有趣話題… – Gea-Suan Lin's BLOG
source link: https://blog.gslin.org/archives/2021/01/22/9930/%e7%b9%9e%e9%81%8e-screensaver-lock-%e7%9a%84%e6%9c%89%e8%b6%a3%e8%a9%b1%e9%a1%8c/
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繞過 Screensaver Lock 的有趣話題...
在 Hacker News Daily 上看到「Screensaver lock by-pass via the virtual keyboard」這篇，裡面這邊題到了 screensaver lock 的有趣話題。
先講嚴肅一點的，這個 bug 被編號為 CVE-2020-25712，問題出在 xorg-x11-server 上：
A flaw was found in xorg-x11-server before 1.20.10. A heap-buffer overflow in XkbSetDeviceInfo may lead to a privilege escalation vulnerability. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
比較有趣的事情是，這個 bug 是小朋友在亂玩時拉出 virtual keyboard 觸發的：
A few weeks ago, my kids wanted to hack my linux desktop, so they typed and clicked everywhere, while I was standing behind them looking at them play... when the screensaver core dumped and they actually hacked their way in! wow, those little hackers...
然後他說他自己搞不出來：
I tried to recreate the crash on my own with no success, maybe because it required more than 4 little hands typing and using the mouse on the virtual keyboard.
另外一個人也說他家小朋友也弄出 segfault 了：
My kids came upon a similar cinnamon-screensaver segfault! I've emailed details of how to reproduce the problem to [email protected].
小朋友超強 XDDD
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Author Gea-Suan LinPosted on January 22, 2021Categories Computer, Joke, Linux, Murmuring, OS, Recreation, Security, SoftwareTags buffer, bypass, cve, flaw, hack, hacker, heap, keyboard, kid, linux, lock, locker, overflow, screensaver, security, segfault, server, virtual, x11, xorgLeave a Reply Cancel reply
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